Copper indium gallium diselenide (CIGS) has become a popular material for the production of thin film photovoltaic (PV) panels. CIGS now holds the world record of 20.1% efficiency for thin film single junction cell efficiency. With any new material comes new challenges, and CIGS has been no exception. While laser scribing has long been the process of choice to form amorphous-silicon (a-Si) and cadmium telluride (CdTe) monolithic interconnects, typically referred to as the P1, P2 and P3 scribe processes, CIGS has presented difficulties in relation to laser processing for the P2 and P3 steps. Thermal effects, giving rise to an increase in electrical conductivity of the film in the laser processed areas, are detrimental to the PV cell electrical performance. Even picosecond laser process results are not completely free of this detrimental heat effect as evidenced by the melted edges and residue. It has been shown that a narrow process window exists in the low nanosecond regime within which a CIGS film can be scribed with virtually no heat effect. Even utilizing the pulse tailoring capabilities of programmable fiber lasers, P2 and P3 scribes in CMS often fail to produce satisfactory results.
Therefore, there is a need in the art for improved methods and systems related to laser scribing of CIGS and other PV materials.